Systems and methods for uav sensor placement

ABSTRACT

An unmanned aerial vehicle (UAV) (200, 300, 400, 700, 800, 1000, 1200, 1500) can include a central body (202, 302, 402, 702, 802, 1002, 1202, 1502), a plurality of rotors, and a plurality of arms (204, 306, 406, 706, 806, 1006, 1206, 1506) extending from the central body (202, 302, 402, 702, 802, 1002, 1202, 1502), where each arm of the plurality of arms (204, 306, 406, 706, 806, 1006, 1206, 1506) is configured to support one or more of the plurality of rotors. The UAV may include at least one sensor (208, 318, 418, 718, 818, 822, 1022, 1218, 1222, 1518) located on the UAV (200, 300, 400, 700, 800, 1000, 1200, 1500) outside of a keep-out zone, where the keep-out zone is defined at least in part by (1) a plurality of rotor disks, a rotor disk of the plurality of rotor disks for each of the plurality of rotors, each rotor disk corresponding to an area that is swept by one or more rotor blades (206, 308, 408, 708, 808, 1008, 1208, 1508) of a corresponding rotor when the rotor blades (206, 308, 408, 708, 808, 1008, 1208, 1508) are spun, and (2) a shape that is formed by adjoining respective centers of adjacent rotor disks.

BACKGROUND OF THE INVENTION

An unmanned vehicle such as an unmanned aerial vehicle (UAV) can be usedfor various applications, such as performing surveillance,reconnaissance, and exploration tasks in a wide variety of environmentsfor military and civilian applications. A UAV may also be used invarious delivery applications, including delivery of chemicals to cropsin agriculture. A UAV may comprise one or more sensors for collectinginformation regarding its environment and the UAV may employ suchinformation for obstacle avoidance. The ability of a UAV to avoidobstacles during flight may be advantageous, for example to both preventdamage to the UAV and facilitate completion of its tasks.

SUMMARY OF THE INVENTION

The ability of a UAV to avoid obstacles in its surrounding environmentmay depend in part on the quality of information collected by one ormore sensors positioned on the UAV regarding the environment surroundthe UAV. Interference from one or more components of the UAV and/or as aresult of operation of the UAV may degrade the quality of informationcollected by the one or more sensors. According to some aspects, anunmanned aerial vehicle (UAV) is provided. The UAV may demonstrateimproved obstacle avoidance capabilities, such as due to an improvementin the quality of information provided by one or more sensors on theUAV. The UAV may comprise a central body, a plurality of rotors, aplurality of arms extending from the central body, wherein each arm ofthe plurality of arms is configured to support one or more of theplurality of rotors. The UAV may comprise at least one sensor located onthe UAV outside of a keep-out zone, wherein the keep-out zone is definedat least in part by (1) at least a portion of a plurality of rotordisks, a rotor disk of the plurality of rotor disks for each of theplurality of rotors, each rotor disk corresponding to an area that isswept by one or more rotor blades of a corresponding rotor when therotor blades are spun, and (2) a shape that is formed by adjoiningrespective vertical center axes of adjacent rotor disks.

In some embodiments, the at least one sensor is configured to sense anenvironment in which the UAV is configured to operate, by detecting oneor more obstacles within the environment.

In some embodiments, the at least one sensor comprises at least one of aproximity sensor, an image sensor, and a global positioning system (GPS)sensor.

In some embodiments, the at least one sensor is configured to measure atleast one of acoustic wave signals, and electromagnetic wave signalsfrom the environment. In some embodiments, the electromagnetic wavesignals comprise at least one of radio waves, microwaves, infraredwaves, visible light waves, ultraviolet waves, X-ray waves, and gammaray waves.

In some embodiments, at least a portion of at least two of the pluralityof rotor disks lie on a same plane. In some embodiments, at least aportion of at least two of the plurality of rotor disks lie on differentplanes.

In some embodiments, the at least one sensor is located further awayfrom the central body than the one or more rotor disks on each of theplurality of arms. In some embodiments, each of the plurality of rotordisks comprises an outer portion and an inner portion opposite the outerportion, the outer portion being further away from the central body thanthe inner portion, and wherein the keep-out zone is defined at least inpart by the outer portion of each of the plurality of rotor disks. Insome embodiments, the at least one sensor is located outside of thekeep-out zone and is facing away from the central body, the keep-outzone being defined at least in part by the outer portion of the rotordisk.

In some embodiments, the shape formed by adjoining respective verticalcenter axes of adjacent rotor disks is a regular shape. In someembodiments, the shape formed by adjoining respective vertical centeraxes of adjacent rotor disks is an irregular shape.

In some embodiments, the at least one sensor is located on a distal endof a corresponding one of the plurality of arms.

In some embodiments, the at least one sensor is located on a componentof the UAV, and wherein the component is selected from a groupconsisting of a protective cover and a landing stand. In someembodiments, the at least one sensor is on an outer surface of theprotective cover facing away from the central body.

In some embodiments, the protective cover is attached to the centralbody of the UAV. In some embodiments, the protective cover is attachedto a distal end of an arm. In some embodiments, the protective cover isconfigured to surround the central body, the plurality of arms, and theplurality of rotors of the UAV. In some embodiments, the protectivecover is configured to protect the UAV from external impact. In someembodiments, the protective cover is configured to protect at least oneof the plurality of rotors from external impact. In some embodiments,the protective cover comprises a portion which is further away from thecentral body than the one or more rotor disks on a corresponding arm. Insome embodiments, the protective cover is positioned adjacent to andpartially surrounds the at least one of the plurality of rotor disks.

In some embodiments, the UAV may further comprise a landing standoperably coupled to at least one of the central body and an arm of theUAV, wherein the at least one sensor is attached to the landing stand.In some embodiments, the landing stand is rigidly attached to a distalend of the arm. In some embodiments, the landing stand is locatedfurther away from the central body than one or more rotor disks of theone or more rotors on a corresponding arm. In some embodiments, thelanding stand extends downward from a distal end of the correspondingarm.

In some embodiments, the landing stand is rotatably coupled to thecentral body. In some embodiments, the landing stand is configured to berotatable towards the central body to extend laterally from the centralbody when the UAV is in a flight configuration, wherein the at least onesensor is located on a portion of the landing stand outside the keep-outzone when the UAV is in the flight configuration. In some embodiments,the landing stand is configured to be rotatable away from the centralbody to extend below the central body when the UAV is in a landingconfiguration, wherein the at least one sensor is located on a portionof the landing stand within the keep-out zone when the UAV is in thelanding configuration.

In some embodiments, the component is integrally formed with at leastone of the plurality of arms, and the central body.

In some embodiments, the component is operably coupled to at least oneof the plurality of arms, and the central body. In some embodiments, acoupling between the component and the at least one of the pluralityarms and the central body comprises at least one of a mechanicalcoupling and an electrical coupling. In some embodiments, the componentcomprises a plurality of parts configured to be assembled onto thecentral body.

In some embodiments, the at least one sensor is located on one or moreof the plurality of arms, and wherein at least one of the plurality ofarms comprises a hollow cavity that allows electrical wiring to passthrough from the central body to the at least one sensor. In someembodiments, electrical wiring is (1) routed from the central bodythrough a hollow cavity of an arm, (2) exits the hollow cavity at adistal end of an arm, and (3) wraps around an outer portion of thecomponent to connect to the at least one sensor. In some embodiments,electrical wiring is (1) routed from the central body and (2) wrapsaround an outer portion of the component and an arm to connect to the atleast one sensor.

In some embodiments, the component comprises a hollow cavity that allowselectrical wiring to pass through from the central body to the at leastone sensor. In some embodiments, the component and an arm each comprisesa hollow cavity that allows the electrical wiring to pass through fromthe central body to the at least one sensor.

In some embodiments, electrical wiring connects the at least one sensorto one or more processors in the central body. In some embodiments, theone or more processors are located in a flight controller and/orinertial measurement unit (IMU) of the UAV.

In some embodiments, the arm and/or central body comprises a firstconnector having a first set of electrical wiring, and wherein thecomponent comprises a second connector having a second set of electricalwiring.

According to some aspects, a method of assembling an unmanned aerialvehicle (UAV) is provided. The method of assembling may compriseattaching to a central body of the UAV to a plurality of arms thatextend from the central body, wherein each arm of the plurality of armsis configured to support one or more rotors, and attaching to the UAV atleast one sensor outside of a keep-out zone, wherein the keep-out zoneis defined at least in part by (1) a rotor disk of each rotor, and (2) ashape that is formed by adjoining respective vertical center axes ofadjacent rotor disks.

In some embodiments, the method may further comprise attaching the atleast one sensor to a distal end of a corresponding one of the pluralityof arms.

In some embodiments, the method may further comprise attaching to theUAV at least one of a protective cover and a landing stand, whereinattaching to the UAV at least one sensor comprises attaching the atleast one sensor to a portion of the protective cover or the landingstand outside of the keep-out zone. In some embodiments, the method mayfurther comprise attaching the at least one sensor to an outer surfaceof the protective cover facing away from the central body.

In some embodiments, the method may further comprise attaching the atleast one sensor to the UAV at a location further away from the centralbody than the one or more rotor disks on each of the plurality of arms.

According to some aspects, a kit is provided. The kit may comprise atleast one sensor that is configured to be attached to an unmanned aerialvehicle (UAV), wherein the UAV comprises a central body and a pluralityof arms extending from the central body, and wherein each arm of theplurality of arms is configured to support one or more rotors; andinstructions for assembling the UAV. When the UAV is assembled accordingto the instructions, the assembled UAV may be characterized in that: theat least one sensor is located on the UAV outside of a keep-out zone,wherein the keep-out zone is defined by (1) a rotor disk of each rotor,or (2) a shape that is formed by adjoining respective vertical centeraxes of adjacent rotor disks.

In some embodiments, the kit may further comprise a protective cover anda landing stand, wherein the assembled UAV is characterized in that theat least one sensor is on a portion of the protective cover or thelanding stand outside of the keep-out zone. In some embodiments, thelanding stand is configured to be rotatably coupled to the central body,the landing stand being configured to be rotatable towards the centralbody to extend laterally from the central body when the UAV is in aflight configuration, wherein the at least one sensor is located on aportion of the landing stand outside the keep-out zone when the UAV isin the flight configuration

In some embodiments, the assembled UAV is characterized in that the atleast one sensor is located on a distal end of an arm. In someembodiments, the at least one sensor comprises at least one of aproximity sensor, an image sensor, and a global positioning system (GPS)sensor.

According to some aspects, a method of environmental sensing using anunmanned aerial vehicle (UAV) may comprise providing at least one sensorconfigured to collect environmental information; and attaching the atleast one sensor to the UAV outside of a keep-out zone, the UAVcomprising a plurality of rotors, wherein the keep-out zone is definedat least in part by (1) a plurality of rotor disks for each of theplurality of rotors, and (2) a shape that is formed by adjoiningrespective vertical center axes of adjacent rotor disks. The at leastone sensor may be attached outside of the keep-out zone to reduce visualobstruction and/or noise interference during collection of theenvironmental information.

In some embodiments, the shape formed by adjoining respective verticalcenter axes of adjacent rotor disks is a regular shape. In someembodiments, the visual obstruction is due to at least one of a locationof (i) the plurality of arms, (ii) the one or more rotors, and (iii) thecentral body of the UAV. In some embodiments, the noise interference isgenerated by rotation of the plurality of rotors during operation of theUAV.

In some embodiments, the method may further comprise attaching to theUAV at least one of a protective cover and a landing stand, whereinattaching the at least one sensor to the UAV comprises attaching the atleast one sensor to a portion of the protective cover or the landingstand outside of the keep-out zone.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe appended claims. A better understanding of the features andadvantages of the present invention will be obtained by reference to thefollowing detailed description that sets forth illustrative embodiments,in which the principles of the invention are utilized, and theaccompanying drawings of which:

FIG. 1 is a schematic diagram of an example of a UAV.

FIG. 2 is a schematic side perspective view of an example of a UAV.

FIG. 3 is a schematic top-down view of an example of a UAV.

FIG. 4 is a schematic top-down view of another example of a UAV.

FIG. 5 is a schematic side cross-sectional view of the UAV of FIG. 4.

FIG. 6 shows a schematic side view and a schematic side cross-sectionalview of an arm and a set of rotor blades of the UAV of FIG. 4.

FIG. 7 is a schematic side cross-sectional view of another example of aUAV.

FIG. 8 is a schematic side cross-sectional view of an example of a UAVcomprising a sensor on a landing stand.

FIG. 9 shows a schematic side view and a schematic side cross-sectionalview of an arm, a set of rotor blades and a landing stand of the UAV ofFIG. 8.

FIG. 10 is a schematic side cross-sectional view of another example of aUAV comprising a sensor on a landing stand, where the landing stand ofthe UAV is in an extended state.

FIG. 11 shows a schematic side view and a schematic side cross-sectionalview of the UAV of FIG. 10, where the landing stand of the UAV is in aretracted state.

FIG. 12 is a schematic top-down view of an example of a UAV comprising aplurality of protective covers.

FIG. 13 is a schematic top-down view of one of the protective covers ofFIG. 12.

FIG. 14 is a schematic top-down view of a portion of the UAV of FIG. 12comprising another example of a protective cover.

FIG. 15 is schematic top-down view of another example of a UAVcomprising a plurality of protective covers.

FIG. 16 shows schematic side cross-sectional views of examples ofprotective covers.

FIG. 17 is an example of a process flow diagram for assembling a UAVhaving one or more features described herein.

FIG. 18 is another example of a process flow diagram for assembling aUAV having one or more features described herein.

FIG. 19 is a schematic diagram of an example of a movable objectincluding a carrier and a payload.

FIG. 20 is a schematic diagram of an example of a system for controllinga movable object.

DETAILED DESCRIPTION OF THE INVENTION

The present disclosure provides improved systems and methods forcollecting information relating to the environment surrounding a UAV.The ability of a UAV to avoid obstacles in its surrounding environmentmay depend in part on the quality of information collected by one ormore sensors positioned on the UAV. Interference from one or morecomponents of the UAV and/or as a result of operation of the UAV maydegrade the quality of information collected by the one or more sensors,reducing the accuracy and/or reliability of the information provided bythe sensors. For example, measurement of one or more parameters by thesensors may be impeded due to visual obstruction by one or more othercomponents of the UAV and/or by noise interference generated byoperation of one or more other components of the UAV. Noise interferencemay include, for example, electromagnetic interference, and/ordistortion due to high pressure air release and/or air flow proximate oradjacent to the sensors. Such degradation in the quality of informationcollected by the sensors may reduce the obstacle avoidance capability ofthe UAV.

A UAV comprising one or more sensors positioned on one or more portionsof the UAV as described herein may demonstrate improved obstacleavoidance capability during operation of the UAV, such as due toimproved accuracy and/or reliability in the information collected by theone or more sensors regarding the physical environment in which the UAVis operating. In some embodiments, a UAV can comprise one or moresensors on one or more portions of the UAV outside of a keep-out zone.The keep-out zone may comprise a space within which undesiredinterference to measurements made by sensors would occur if the sensorswere placed within the space. In some embodiments, the keep-out zone ofa UAV may be selected based on the type of sensors. The keep-out zonemay be selected such that interference from one or more components ofthe UAV to the measurements made by the one or more sensors on the UAVcan be reduced or eliminated.

In some embodiments, the one or more sensors described herein maycomprise at least one sensor configured to collect environmentalinformation. A sensor can be used to detect and/or collect various typesof data regarding the environment surrounding the UAV. In some cases, asensor may experience interference from one or more components of theUAV if positioned within the keep-out zone. For example, a sensor mayexperience physical interference (such as visual obstruction) from oneor more portions of the UAV. A sensor may also experience noiseinterference (e.g., electromagnetic interference, airflow/motor noise)due to operation of the UAV, which may arise due to operation of one ormore sets of rotor blades and/or electronic components of the UAV.

In some embodiments, the sensors may comprise a location sensor (e.g.,global positioning system (GPS) sensors), vision sensor (e.g., imagingdevices capable of detecting visible, infrared, or ultraviolet light,such as cameras), proximity sensor (e.g., ultrasonic sensors),combinations thereof, and/or the like. In some embodiments, the UAV maycomprise two or more types of sensors for collecting informationrelating to the environment surrounding the UAV. For example, in someinstances, the UAV may comprise a two or more sensors selected from thegroup consisting of GPS sensors, image sensors and ultrasonic sensors.In some embodiments, the UAV may comprise a plurality of sensorspositioned on various portions of the UAV outside of the keep-out zone,the plurality of sensors comprising any combination of GPS sensors,image sensors, and ultrasonic sensors.

In some embodiments, other sensors suitable for collecting environmentalinformation useful for obstacle detection may be used. Those other typesof sensors may comprise mobile device transmitters enabling locationtriangulation, a lidar sensor and/or time-of-flight cameras), inertialsensors (e.g., accelerometers, gyroscopes, inertial measurement units(IMUs)), altitude sensors, pressure sensors (e.g., barometers), audiosensors (e.g., microphones) or field sensors (e.g., magnetometers,electromagnetic sensors). In some embodiments, the sensors can include asensor for detecting acoustic wave signals other than an ultrasonicsensor, or a sensor for measuring electromagnetic waves other than a GPSsensor. In some embodiments, the sensors can be configured to measureradio waves, microwaves, infrared waves, visible light, ultravioletwaves, x-ray waves and/or gamma rays waves.

In some embodiments, one or more sensors may be configured to faceoutwardly from the UAV. One or more measuring components of the sensorsmay be configured to face various directions. In some embodiments, atleast a portion of the sensors may be configured to rotate along one ormore axes to facilitate information collection. In some embodiments, oneor more components of a sensor configured for collecting information canchange orientation during operation of the sensors.

Measurements made by an ultrasonic sensor may be degraded due to locallygenerated ultrasonic noise. For example, measurements made by ultrasonicsensors may be distorted due to high pressure air release near thesensors, such as with sensors placed near sources which generate highair flow, including sensors positioned too close to rotor blades of theUAV. Images collected by image sensors may be affected by visualobstruction within the field of view of the image sensors. For example,portions of the UAV may extend into the field of view of image sensorsinappropriately positioned on the UAV such that the portions of the UAVmay obstruct the view of the image sensors. Measurements made by a GPSsensor positioned too close to various electronic components of the UAVmay experience electromagnetic interference from those electroniccomponents.

In some embodiments, a keep-out zone for a UAV can be selected such thatundesired interference to measurements made by the sensors placed on theUAV outside of the keep-out zone may be reduced or eliminated, therebyproviding improved quality in the information collected by the sensors.Measurements made by sensors attached to portions of the UAV within thekeep-out zone may be inaccurate due to visual obstruction by anotherportion of the UAV and/or due to interference from operation of one ormore components of the UAV. A UAV comprising one or more sensorspositioned on one or more portions of the UAV outside of a keep-out zonemay demonstrate improved obstacle avoidance capabilities. In someembodiments, one or more ultrasonic sensors placed on the UAV outside ofthe keep-out zone may experience no or reduced interference from locallygenerated ultrasonic noise. For example, the one or more ultrasonicsensors may be placed at a predetermined distance away from the rotorblades of the UAV such that air flow generated by the spinning rotorblades during flight does not undesirably interfere with measurementsmade by the ultrasonic sensors. In some embodiments, one or more imagesensors may be positioned on the UAV such that parts of the UAV,including one or more arms, landing stands, propulsion units and/or thecentral body, do not lie in the field of view of the image sensor. Asused herein, a propulsion unit can include various components whichoperate to generate lift for the UAV, such as including a set of rotorblades and a rotor coupled to the set of rotor blades. In someembodiments, one or more ultrasonic or GPS sensors can be placed on theUAV such that the sensors do not experience significant interferencefrom acoustic or electromagnetic noise, respectively. In someembodiments, one or more GPS sensors may be positioned on the UAV suchthat electromagnetic interference generated by the operation ofelectronic devices of the UAV are reduced or eliminated. For example,one or more GPS sensors may be positioned at a predetermined distanceaway from electronic devices housed within the central body of the UAV.

In some embodiments, the keep-out zone may comprise a rotor blades spinspace for each set of rotor blades of the UAV. A rotor blades spin spacemay comprise a rotor disk for a corresponding set of rotor blades. Arotor blades spin space may be a space through which the set of rotorblades are spun. In some embodiments, the keep-out zone may comprise aninterference space. In some cases, a rotor blades spin space can belarger than the rotor disk of the corresponding set of rotor blades. Insome embodiments, the interference space may comprise a space whichencompasses or substantially encompasses the central body of the UAV. Insome embodiments, the interference space may comprise a lateral boundarycomprising sides which extend between adjacent propulsion units. In someembodiments, the keep-out zone may comprise both a rotor blades spinspace for each set of rotor blades of the UAV and an interference space.For example, one or more sensors positioned on the UAV outside of boththe rotor blades spin spaces and the interference space may demonstrateimproved accuracy in the information collected regarding the environmentsurrounding the UAV, thereby providing a UAV demonstrating improvedability to avoid obstacles.

The UAVs described herein may be quadcopters comprising a central body.It will be understood that one or more features described herein may beapplied to UAVs having other configurations, such as UAV with fewer ormore propulsion units, and/or UAVs with a central body comprising moreor fewer lateral surfaces.

FIG. 1 is a schematic diagram of a UAV 100. The UAV 100 can have aplurality of sensors 104 positioned on respective portions of the UAV100. In some embodiments, each of the plurality of sensors 104 may beplaced on a portion of the UAV 100 that is outside of a keep-out zone106. For example, the plurality of sensors 104 may be positioned onportions of the UAV 100 in zone 102. As shown in FIG. 1, zone 102 maycomprise portions of the UAV 100 that lie outside of the keep-out zone106. Placement of the sensors 104 in zone 102 outside of the keep-outzone 106 may reduce or eliminate adverse effects on the sensormeasurements by one or more portions of the UAV 100 and/or as a resultof the operation of one or more portions of the UAV 100, such that eachof the plurality of sensors 104 can provide measurements having desiredlevels of accuracy.

In some embodiments, the sensors 104 can be configured to collectinformation regarding the environment surrounding the UAV 100. In somecases, the sensors 104 can be used for obstacle avoidance. For example,the sensors 104 can be configured to measure various parameters fordetermining the presence of and/or a distance of the UAV 100 from one ormore obstacles. The UAV 100 may include an obstacle avoidance systemcomprising the plurality of sensors 104, where the obstacle avoidancesystem is configured to receive information collected by the sensors 104regarding the environment surrounding the UAV 100, and to adjust themovement of the UAV 100 in response to the information so as to avoidthe obstacles in the environment around the UAV 100. In someembodiments, the sensors 104 can be configured to collect informationregarding the surrounding environment, such that the UAV 100 can detectone or more stationary and/or movable objects in the vicinity of the UAV100 so as to avoid the one or more obstacles.

The plurality of sensors 104 may comprise various types of sensors. Theplurality of sensors 104 may be the same type of sensors or may comprisedifferent types of sensors. As described herein, the plurality ofsensors 104 may comprise one or more types of sensors suitable forcollecting information regarding the environment surrounding the UAV100. In some embodiments, the sensors 104 can comprise image sensors,GPS sensors, ultrasonic sensors, or a combination thereof. In someembodiments, the UAV can include a combination of image sensors, GPSsensors and ultrasonic sensors. FIG. 2 is a schematic diagram of a UAV200 comprising a central body 202, and a plurality of arms 204 extendingoutwardly from the central body 202. The central body 202 of the UAV 200shown in FIG. 2 may have a polyhedron shape having two pairs of opposingside surfaces, 202A, 202B and 202C, 202D. The UAV 200 may include fourarms 204, one of the four arms 204 extending outwardly from each of theside surfaces 202A, 202B, 202C and 202D. The UAV 200 can include aplurality of sets of rotor blades 206 configured to provide lift for theUAV 200. As shown, the UAV 200 can have four sets of rotor blades 206,where a set of rotor blades 206 can be coupled to a corresponding arm204. The pitch, roll, and yaw of the UAV 200 can be adjusted byadjusting the rotational speed and/or directions of one or more of thefour sets of rotor blades 206. The UAV 200 can have a plurality ofsensors 208. The plurality of sensors 208 can be located outside of akeep-out zone 210. For example, the UAV 200 can include two sensors 208,each on a portion of an arm 204 that is outside of the keep-out zone210. The keep-out zone 210 is shown having a rounded shape, such as asphere. The sensors 208 can be positioned on the UAV 200 outside of thekeep-out zone 210 such that interference to measurements made by thesensors 208 can be reduced or eliminated, such as interference from oneor more portions of the UAV 200 or as a result of operation of one ormore portions of the UAV 200.

A keep-out zone can comprise various shapes. In some embodiments, thekeep-out zone need not be a sphere. The keep-out zone may be defined byany shape on a 2-dimensional plane or in 3-dimensional space. In somecases, the shape of the keep-out zone may be selected based on aconfiguration of the UAV and/or the one or more sensors used. Forexample, the keep-out zone may be selected based on the number and/ortypes of electronic devices housed within the central body of the UAV,and/or the type of information collected by the sensors. Variousconfigurations of the sensor placement on the UAV may be contemplated.In some embodiments, one or more sensors may be positioned on portionsof the UAV outside of the keep-out zone other than on the arms. Forexample, one or more sensors may be positioned on portions of a landingstand and/or a protective cover of the UAV outside of the keep-out zone.

A central body of a UAV can have various shapes. In some embodiments,the central body may have a shape other than a polyhedron. In someembodiments, the central body can comprise one or more curves. In someembodiments, the central body can comprise a rounded shape. In someembodiments, one or more arms of the UAV may extend from the UAV otherthan from a lateral surface of the UAV. In some embodiments, an arm canextend from an edge of the UAV. In some embodiments, each of theplurality of the arms may extend from an edge of the UAV.

FIG. 3 is a top-down schematic view of an example of a UAV 300. The UAV300 may comprise a central body 302 and a plurality of arms 306extending outwardly from the central body 302. In some embodiments, thecentral body 302 can have a quadrilateral shape, adjacent sides of thequadrilateral shape being joined at corresponding connection portions304. In some embodiments, the adjacent sides of the central body 302 canbe perpendicular or substantially perpendicular to one another such thatthe central body 302 comprises a rectangular shape. In some embodiments,the four sides of the central body 302 can have the same length suchthat the central body 302 comprises a square. As shown in FIG. 3, theUAV 300 may comprise four arms 306, an arm 306 extending outwardly fromeach of the four sides of the central body 302. In some embodiments,each arm 306 may be perpendicular or substantially perpendicular to theside of the central body 302 from which it extends.

It will be understood that although the central body of the UAV isdescribed herein primarily as having a quadrilateral shape, the centralbody of the UAV may have a shape other than a quadrilateral. The centralbody of the UAV may comprise more or fewer sides. In some embodiments,the central body of the UAV may comprise a shape comprising one or morearcs. In some embodiments, the central body may comprise a roundedshape. In some embodiments, one or more arms of a UAV may extend from acurved edge of the central body.

In some embodiments, the UAV 300 may comprise a plurality of sets ofrotor blades 308. Each set of rotor blades 308 may be coupled to acorresponding arm 306. For example, the UAV 300 may comprise one set ofrotor blades 308 coupled to each of the four arms 306 such that the UAV300 is a quadcopter. In some embodiments, UAV 300 comprises a rotor foreach of the sets of rotor blades 308, each of the sets of rotor blades308 coupled to a corresponding rotor. For example, a rotor may be oneach of the plurality of arms 306 for coupling to a set of rotor blades308.

In some embodiments, one or more arms of a UAV may comprise more thanone rotor such that more than one set of rotor blades may be coupled tothe one or more arms.

Referring to FIG. 3, the UAV 300 can comprise a plurality of sensors 318configured to measure parameters of the environment surrounding the UAV300. As described in further detail elsewhere herein, the plurality ofsensors 318 may comprise a variety of types of sensors, including animage sensor, an ultrasonic sensor and/or a GPS sensor. The plurality ofsensors 318 can be positioned on portions of the UAV 300 outside of akeep-out zone 310. As shown in FIG. 3, in some embodiments, the UAV 300can have four sensors 318, one of the sensors 318 being positioned on aportion of each of the four arms 306 outside of the keep-out zone 310.

In some embodiments, the keep-out zone 310 may comprise a rotor bladesspin space 312 for each of the sets of rotor blades 308, and aninterference space 314. For example, the keep-out zone 310 may comprisefour rotor blades spin spaces 312, one for each of the four sets ofrotor blades 308. In some embodiments, a rotor blades spin space 312 cancomprise a rotor disk of the corresponding set of rotor blades 308, orthe space through which the corresponding set of the rotor blades 308travels when the set of rotor blades 308 are spun during flight. In someembodiments, the rotor blades spin space 312 of a set of rotor blades308 is the rotor disk of the set of rotor blades 308. In someembodiments, each of the plurality of rotor disks corresponding to thesets of rotor blades 308 may comprise a portion proximate to the centralbody 302, or an inner portion of the rotor disk. Each of the rotor disksmay also comprise a portion opposite the portion proximate to thecentral body 302, or an outer portion of the rotor disk. For example, aninner portion of a rotor disk may comprise the portion of the rotor diskclosest to the central body. An outer portion of a rotor disk maycomprise the portion of the rotor disk further away from the centralbody. In some embodiments, the keep-out zone 310 is defined in part bythe outer portion of each of the plurality of rotor disks. In someembodiments, the keep-out zone 310 is defined in part by the portion ofeach of the plurality of rotor disks furthest away from the central body302.

In some embodiments, each of the sensors 318 is located further awayfrom the central body 302 than the one or more rotor disks. Each of therotor blades spin spaces 312 may be the space swept by the correspondingset of rotor blades 308 when the set of rotor blades are spun such thatthe rotor blades spin spaces 312 each comprise a circular shape, adiameter of the rotor blades spin space 412 being dependent on a lengthof a rotor blade of the corresponding set of rotor blades 308. As usedherein, a length of a rotor blade refers to a longest dimension of therotor blade. For example, the diameter may be the sum of the longestdimension of two rotor blades. Each of the rotor blades spin spaces 312may be the rotor disk of the corresponding set of rotor blades 308 suchthat a height of a rotor blades spin space 312 can depend upon a widthof a rotor blade of the corresponding set of rotor blades 308, such as alargest width of the rotor blade. As used herein, a width of a rotorblade is a dimension of the rotor blade which extends in a directionperpendicular or substantially perpendicular to the length of the rotorblade. In some embodiments, the rotor disk of a set of rotor blades 308may extend at least partially over the central body 302 of the UAV. Forexample, the rotor disk of each of the four sets of rotor blades 308 mayextend at least partially over the central body 302. In someembodiments, at least one of the rotor disks does not extend over thecentral body 302. In some embodiments, none of the rotor disks for thefour sets of rotor blades 308 comprises any portion which extends overthe central body 302. In some embodiments, two or more of the rotordisks may comprise at least a portion which is on the same horizontalplane with a portion of another of the rotor disks. In some embodiments,each of the four sets of rotor blades 308 are at the same height suchthat all corresponding portions of the rotor disks are horizontallycoplanar or substantially horizontally coplanar. In some embodiments,one or more of the rotor disks comprises no portion which ishorizontally coplanar with any portion of another one of the rotordisks. In some embodiments, two or more of the rotor disks may compriserespective portions which are on different horizontal planes. Forexample, all portions of one or more of the rotor disks may be at aheight higher than any portion of one or more other of the rotor disks.In some embodiments, as described in further details herein, a rotorblades spin space may comprise a space larger than the rotor disk of acorresponding set of rotor blades. For example, a rotor blades spinspace may comprise one or more dimensions longer than a correspondingdimension of the rotor disk. In some embodiments, a rotor blades spinspace may have an upper boundary above the top surface of the rotordisk, a lower boundary below the bottom surface of the rotor disk,and/or a lateral boundary beyond a lateral surface of the rotor disk.

In some embodiments, the configuration of a rotor blades spin space maybe selected based on the type of sensor used. For example, a keep-outzone for a UAV comprising a plurality of ultrasonic sensors may comprisea rotor blades spin space having an upper boundary, a lower boundary,and/or a lateral boundary of a rotor blades spin space above the topsurface, below the bottom surface, and/or beyond a lateral surface,respectively, of the rotor disk, such that interference due to air flowgenerated by the rotor blades can be reduced or eliminated. In someembodiments, a keep-out zone for a UAV comprising only one or more ofimage sensors and GPS sensors may comprise a rotor blades spin spacewhich is the rotor disk of the corresponding set of rotor blades, suchthat the field of view of the image sensors or measurements made by theGPS sensors are not degraded due to obstruction from one or morecomponents of the UAV, such as by the spinning of the rotor blades,without unduly limiting portions of the UAV on which the sensors may beplaced.

In some embodiments, the interference space 314 may be bounded by alateral boundary comprising sides 316. For example, the interferencespace 314 can be defined at least in part by a lateral boundarycomprising sides 316 which extend between adjacent propulsion units ofcorresponding rotor blades 308. In some embodiments, the sides 316extend between vertical center axes of adjacent rotor disks and/oradjacent propulsion units, of corresponding sets of rotor blades 308.For example, a portion of each of the adjacent propulsion units may beoutside of the interference space 314. In some embodiments, the sides316 may extend between the vertical center axes of adjacent rotor blades308. In some embodiments, the sides 316 may be linear or substantiallylinear. In some embodiments, the interference space 314 may have aquadrilateral shape. In some embodiments, the interference space 314comprises a square. For example, the central body 302 may comprise asquare shape, each of the four arms 306 extending perpendicularly orsubstantially perpendicularly from the four sides of the central body302, such as a center or substantially a center of a horizontaldimension of each of the four sides, and each of the four sets of rotorblades 308 being equidistant or substantially equidistant from thecentral body 302 such that the interference space 314 comprises a squareshape. In some embodiments, the sides 316 may be non-linear. In someembodiments, one or more of the sides 316 may comprise an arc, such as aconvex and/or concave curve. The configuration of the sides may beselected based on, for example, a type of sensor being used. Forexample, the configuration of the sides may be selected such that thetype or types of sensor used do not experience undesired interferencewhen positioned outside of the keep-out zone 310. In some embodiments, aconfiguration of the sides may be selected such that an image sensor,ultrasonic sensor and/or GPS sensor does not experience undesired visualobstruction, acoustic noise or electromagnetic interference from one ormore other portions of the UAV 310.

In some embodiments, an interference space may comprise a regular shape,such as a rectangle. As described herein, in some embodiments, theinterference space may comprise a square. In some embodiments, aninterference space may comprise an irregular shape, such as an irregularquadrilateral.

In some embodiments, at least a portion of the central body 302 iswithin the interference space 314. In some embodiments, the connectionportions 304 of the adjacent sides of the central body 302 can be on thelateral boundary of the interference space 314, such as on acorresponding side 316 of the lateral boundary of the interference space314. In some embodiments, the connection portions 304 may be completelywithin the interference space 314, for example within the space boundedby the sides 316 of the lateral boundary of the interference space 314.

In some embodiments, the keep-out zone 310 comprises both the rotorblades spin spaces 312 and the interference space 314. For example,sensors may be placed on portions of the UAV 300 that are outside ofboth the rotor blades spin spaces 312 and the interference space 314. Insome embodiments, sensors are located further away from the central body302 than any portion of rotor disks of the sets of rotor blades 308. Insome embodiments, measurements made by sensors positioned on portions ofthe UAV 300 outside of both of the interference spaces 314 and rotorblades spin space 312 may experience diminished or no interference byanother portion of the UAV 300 and/or due to the operation of anyportion the UAV 300.

FIG. 4 is a top-down schematic view of another example of a UAV 400 anda keep-out zone 410. The UAV 400 can include a central body 402 having aquadrilateral shape, the adjacent sides of the quadrilateral meeting atthe four connection portions 404, where an arm 406 extends outwardlyaway from the central body 402 at each of the connection portions 404.The UAV 400 may comprise a propulsion unit on each of the four arms 406.A set of rotor blades 408 of the propulsion unit may be coupled to eachof the four arms 406 such that the UAV 400 is a quadcopter. As shown inFIG. 4, the UAV 400 may include a plurality of sensors 418 positioned onportions of the UAV 400 outside of the keep-out zone 410. A sensor 418may be placed on each of the four arms 406 outside of the keep-out zone410. In some embodiments, the keep-out zone 410 comprises aninterference space 414 and a plurality of rotor blades spin spaces 412.For example, each of the sensors 418 may be placed on a distal portionof each of the four arms 406, where the distal portion of each of thefour arms 406 is outside both the rotor blades spin spaces 412 and theinterference space 414.

In some embodiments, as shown in FIG. 4, the interference space 414 maycomprise a lateral boundary comprising sides 416 which extend betweenadjacent sets of rotor blades 408, such that lateral sides of thecentral body 402 are completely or substantially completely within theinterference space 414. In some embodiments, the sides 416 extendbetween vertical center axes of adjacent rotor disks of correspondingsets of rotor blades 408. In some embodiments, the sides 416 may extendbetween corresponding center axes of adjacent sets of rotor blades 408.In some embodiments, at least a portion of a lateral side of the centralbody 402 may be a distance d1 from a portion of a corresponding side 416of the interference space 414. In some embodiments, one or more lateralsides of the central body 402 are parallel or substantially parallel toa corresponding side 416 of the lateral boundary of the interferencespace 414. In some embodiments, each of the four lateral sides of thecentral body 402 can be parallel or substantially parallel to acorresponding side 416 of the interference space 414 such that each ofthe four lateral sides of the central body 401 are at a distance d1 froma corresponding side 416. In some embodiments, the central body 402 mayhave a square shape and each of the sets of rotor blades 408 may beequidistant or substantially equidistant from a corresponding connectionportion 404 of the central body 402 such that the sides 416 of thelateral boundary of the interference space 414 form a square shape.

In some embodiments, the keep-out zone 410 may comprise a rotor bladesspin space 412 for each set of rotor blades 408. In some embodiments, arotor blades spin space 412 may comprise a rotor disk for acorresponding set of rotor blades 408. As shown in FIG. 4, a rotorblades spin space 412 may be the rotor disk of the corresponding set ofrotor blades 408. For example, the rotor blades spin space 412 maycomprise a circular shape, a diameter of the rotor blades spin space 412being a longest dimension of the set of rotor blades 408, such as atotal length of the set of rotor blades 408. A height of the rotorblades spin space 412 may depend upon a largest width of the set ofrotor blades 408. As described herein, in some embodiments, a rotorblades spin space may be larger than the rotor disk of the correspondingset of rotor blades.

FIG. 5 is a side cross-sectional view of the UAV 400 and the keep-outzone 410 described with reference to FIG. 4. The cross-sectional view ofFIG. 5 is taken along the A-A line shown in FIG. 4, the A-A lineextending across opposing connection portions 404 of the central body402. The cross sectional view may comprise a cross-sectional view ofboth the interference space 414 and rotor blades spin spaces 412. Thekeep-out zone 410 can have a top boundary 410A and a bottom boundary410B. In some embodiments, the top boundary 410A of the keep-out zone410 may comprise a portion which is above each of the rotor blades 408.In some embodiments, the keep-out zone 410 may comprise a portion whichextends above the rotor disk of each of the sets of rotor blades 408.For example, the top boundary 410A of the keep-out zone 410 may have aportion which is a distance d2 above the top edge of each of the sets ofrotor blades 408. In some embodiments, the top boundary 410A can have aportion which is a distance d3 above the top surface of the central body402. In some embodiments, the distances d2 and d3 may be selected suchthat the top boundary 410A may comprise a portion that is planar orsubstantially planar. In some embodiments, the top boundary 410A of thekeep-out zone 410 may be at a distance d2 above a top edge of each ofthe sets of rotor blades 408 and a distance d3 above the top surface ofthe central body 402 such that the top boundary 410A is planar orsubstantially planar. In some embodiments, a portion of the top boundary410A may be at the top edge of each of the sets of rotor blades 408, forexample, such that d2 for the portion of the top boundary 410A is zero.In some embodiments, the top boundary 410A may comprise a portion whichis coplanar or substantially coplanar with the top surface of the rotordisks of each of the sets of rotor blades 408. In some embodiments, thetop boundary 410A can comprise a portion which is at the top surface ofthe central body 402, for example, such that d3 is zero at the portionof the top boundary 410A. In some embodiments, the top boundary 410A cancomprise a portion which is coplanar or substantially coplanar with thetop surface of the central body 402. In some embodiments, the topboundary 410A is planar or substantially planar and is coplanar with thetop surface of the rotor disks of the sets of rotor blades 408. In someembodiments, the top boundary 410A can be non-planar, for examplecomprising one or more portions which are curved.

In some embodiments, the bottom boundary 410B may comprise a portionwhich is below each of the arms 406. The bottom boundary 410B maycomprise a portion which is a distance d4 below the bottom surface ofeach of the arms 406. The bottom boundary 410B may comprise a portionwhich is a distance d5 below the bottom surface of the central body 402.In some embodiments, the distances d4 and d5 are selected such that thebottom boundary 410B can comprise a portion which is planar orsubstantially planar. In some embodiments, the distances d4 and d5 areselected such that the bottom boundary 410B can be planar orsubstantially planar. In some embodiments, the bottom boundary 410B maycomprise a portion at the bottom surface of the central body 402, forexample such that d5 is zero at the portion of the bottom boundary 410B.In some embodiments, the bottom boundary 410B may comprise a portion ata bottom surface of one or more of the arms 406, for example such thatd4 is zero at the portion of the bottom boundary 410B. In someembodiments, the bottom boundary 410B may be coplanar or substantiallycoplanar with the bottom surface of the central body 402. In someembodiments, the bottom boundary 410B can be non-planar, for examplecomprising one or more portions which are curved. In some embodiments,the distances d2, d3, d4 and/or d5 may be selected based on the type ortypes of sensors used such that sensors placed outside of the keep-outzone 410 can provide desired information for obstacle avoidance, withoutunduly limiting the positions of the UAV on which the sensors may beplaced.

In some embodiments, the keep-out zone 410 can comprise a lateralboundary 410C. For example, sides 416 of the lateral boundary of theinterference space 414 adjacent to one another may meet at the lateralboundary 410C. In some embodiments, the lateral boundary 410C maycomprise portions which run through each of the propulsion units of theUAV 400. For example, the lateral boundary 410C may comprisecorresponding portions which run through the center axes of rotor disksof each of the sets of rotor blades 408 and/or through the center axesof each of the sets of rotor blades 408. In some embodiments, thelateral boundary 410C may comprise one or more portions which arelinear. Referring to FIG. 5, the rotor blades spin spaces 412 may eachbe the rotor disk for the corresponding set of rotor blades 408 suchthat the lateral boundary 410C comprises a portion of the boundary ofthe rotor disks. For example, the lateral boundary 410C may comprise alinear or substantially linear portion extending from the top of each ofthe rotor disks to the top boundary 410A, and a linear or substantiallylinear portion extending from the bottom of the rotor disks to thebottom boundary 410B.

In some embodiments, a lateral boundary may comprise one or moreportions which are non-linear. For example, a lateral boundary maycomprise one or more portions comprising an arc.

Referring to FIG. 6 Part A, a schematic side view of an arm 406 of theUAV 400 is shown. The arm 406 can have a proximal portion 406A proximateto the central body 402 of the UAV 400 and an opposing distal portion406B away from the central body 406. A set of rotor blades 408 can becoupled to the distal portion 406B of the arm 406. As shown in FIG. 6Part A, the set of rotor blades 408 and a portion of the arm 406,including the proximal portion 406A of the arm 406, may be within thekeep-out zone 410. The distal portion 406B of the arm 406 may comprise aportion 406C which is outside of the keep-out zone 410. A sensor 418 maybe positioned on the arm 406 at a position within the portion 406C suchthat the sensor 418 is outside of the keep-out zone 410. In someembodiments, the sensor 418 may be positioned at a distal end 406D ofthe arm 406.

FIG. 6 Part B shows a schematic side cross-sectional view of the arm406. In some embodiments, the arm 406 comprises at least a portion thatis hollow such that at least a portion of the wiring 430 to providecommunication between one or more controllers of the UAV 400 and thesensor 418 and/or to provide electrical power to the sensor 418 may behoused within the arm 406. In some embodiments, the controller maycomprise one or more processors. In some embodiments, the controllercomprises a flight controller and/or an inertial measurement unit (IMU).For example, the wiring 430 may provide communication between the sensor418 with one or more processors of a flight controller and/or an IMUwithin the central body 402. In some embodiments, the sensor 418 may beat a distal end 406D of the arm 406 and an entire length of the arm 406may be hollow such that wiring 430 for communication between the sensor418 and one or more controllers housed within the central body 402 mayextend from the central body 402 to the sensor 418 through the hollowshaft within the arm 406. In some embodiments, the arm 406 may compriseat least a portion which is not hollow such that at least a portion ofthe wiring 430 is routed on an outer surface of the arm 406.

In FIG. 7, a side cross-sectional view of another example of a UAV 700and a keep-out zone 710 is shown. As shown in FIG. 7, the UAV 700 maycomprise a central body 702. In the cross-sectional view shown in FIG.7, an arm 706 can extend outwardly from each of two opposing lateralsurfaces of the central body 702, and a set of rotor blades 708 can becoupled to each of the arms 706. The central body 702 of the UAV 700 maycomprise a quadrilateral shape such that the UAV 700 comprises a totalof four arms extending outwardly from each of the four lateral sides ofthe central body 702, each of the arms 706 coupled to a correspondingset of rotor blades 708. The side cross-sectional view of FIG. 7 may betaken along a plane extending between opposing sets of rotor blades 708coupled to arms 706 extending from opposing lateral surfaces of thecentral body 702. The UAV 700 may comprise a sensor 718 positioned oneach of the arms 706 outside of the keep-out zone 710.

The keep-out zone 710 may comprise an interference space and a rotorblades spin space for each of the sets of rotor blades 708 of the UAV700. The cross-sectional view of the keep-out zone 710 can include across-sectional view of a rotor blades spin space for each of the twosets of rotor blades 708 shown in FIG. 7 and the interference space. Asdescribed herein, in some embodiments, a rotor blades spin space for aset of rotor blades may be larger than a corresponding rotor disk of theset of rotor blades. For example, a rotor blades spin space may extendvertically and/or laterally beyond the corresponding rotor disk. Forexample, the rotor blades spin space may extend a distance above the topsurface, below the bottom surface and/or laterally beyond a lateralsurface of the rotor disk. Referring to FIG. 7, a rotor blades spinspace for a set of rotor blades 708 may extend above, below and/orlaterally beyond the rotor disk of each of the two sets of rotor blades708 such that the keep-out zone 710 may comprise a top boundary 710Ahaving a portion above the top edge of the sets of rotor blades 708, abottom boundary 710B comprising a portion below the bottom edge of thesets of rotor blades 708 and/or a lateral boundary 710C, 710D or 710Ecomprising a portion to a side of a lateral edge of the sets of rotorblades 708.

In some embodiments, the top boundary 710A of the keep-out zone 710 maycomprise a portion which is at a distance d6 above the top edge of eachof the sets of rotor blades 708. In some embodiments, the bottomboundary 710B may comprise a portion which is a distance d7 above thetop surface of the central body 702. In some embodiments, the topboundary 710A is planar or substantially planar. In some embodiments,the bottom boundary 710B may comprise a portion which is below each ofthe arms 706. The bottom boundary 710B may comprise a portion which is adistance d8 below the bottom surface of each of the arms 706. In someembodiments, the bottom boundary 710B may comprise a portion which isbelow the bottom surface of the central body 702. For example, thebottom boundary 710B may comprise a portion which is a distance d9 belowthe bottom surface of the central body 702.

In some embodiments, a portion of the top boundary 710A may be at thetop edge of each of the sets of rotor blades 708, for example, such thatd6 for the portion of the top boundary 710A is zero. In someembodiments, the top boundary 710A may comprise a portion which iscoplanar or substantially coplanar with the top surface of the rotordisks of each of the sets of rotor blades 708. In some embodiments, thetop boundary 710A can comprise a portion which is at the top surface ofthe central body 702, for example, such that d7 is zero at the portionof the top boundary 710A. In some embodiments, the top boundary 710A cancomprise a portion which is coplanar or substantially coplanar with thetop surface of the central body 402. In some embodiments, the topboundary 710A is planar or substantially planar and is coplanar with thetop surface of the rotor disks of the sets of rotor blades 708. In someembodiments, the top boundary 710A can be non-planar, for examplecomprising one or more portions which are curved.

In some embodiments, the distances d8 and d9 are selected such that thebottom boundary 710B can comprise at least a portion which is planar orsubstantially planar. In some embodiments, the distances d8 and d9 areselected such that the bottom boundary 710B can be planar orsubstantially planar. In some embodiments, the bottom boundary 710B maycomprise at least a portion at the bottom surface of the central body702, for example such that d9 is zero at the portion of the bottomboundary 710B. In some embodiments, the bottom boundary 710B maycomprise a portion at the bottom surface of one or more of the arms 706,for example such that d8 is zero at the portion of the bottom boundary710B. In some embodiments, the bottom boundary 710B may be coplanar orsubstantially coplanar with the bottom surface of the central body 702.In some embodiments, the bottom boundary 710B can be non-planar, forexample comprising one or more portions which are curved.

In some embodiments, the keep-out zone 710 may comprise a lateralboundary 710C, 710D or 710E comprising at least a portion which is to aside of a lateral edge of the two sets of rotor blades 708 such that thepropulsion units of the UAV 700 are completely or substantially withinthe keep-out zone 710. In some embodiments, a lateral boundary 710C,710D or 710E of the keep-out zone 710 may comprise at least a portionwhich is both above the top edge and to a side of a lateral edge of eachof the sets of rotor blades 708. In some embodiments, the keep-out zone710 may comprise a lateral boundary 710C, 710D or 710E comprising atleast a portion which is below the bottom edge of each of the two setsof rotor blades 708. In some embodiments, a lateral boundary 710C, 710Dor 710E of the keep-out zone 710 may comprise at least a portion whichis both below the bottom edge and to a side of a lateral edge of each ofthe sets of rotor blades 708. In some embodiments, the lateral boundarycan comprise various suitable profiles. In some embodiments, the lateralboundary 710D may comprise a portion which is linear or substantiallylinear. In some embodiments, the lateral boundary 710C or 710E maycomprise a portion which comprises an arc. In some embodiments, thelateral boundary 710C may comprise at least a portion comprising aconcave profile. In some embodiments, the lateral boundary 710E maycomprise at least a portion comprising a convex profile. In someembodiments, the lateral profile 710C or 710E may comprise a curvedprofile such that the propulsion units are entirely or substantiallyentirely within the keep-out zone 710. In some embodiments, the lateralboundary 710D may have a linear or substantially linear profile and isto a side of a lateral edge of each of the sets of rotor blades 708 suchthat the propulsion units are entirely or substantially entirely withinthe keep-out zone 710.

Referring to FIG. 8, a schematic side cross-sectional view of an exampleof a UAV 800 comprising sensors 822 on landing stands 820 of the UAV 800is shown. The UAV 800 may comprise a central body 802 and an arm 806extending outwardly from each of the lateral surfaces of the centralbody 802. In the side cross-sectional view of FIG. 8, an arm 806 isshown as extending outwardly from each of two opposing lateral surfacesof the central body 802. Each of the arms 806 may be coupled to acorresponding set of rotor blades 808. A corresponding landing stand 820may extend from each of the arms 806. The landing stand 820 may not beretractable and/or foldable to a lower profile configuration when thelanding stand 820 is not in-use by the UAV 800, such as during flight.For example, the landing stand 820 may be rigidly attached to the arm806 such that the landing stand 820 may not be rotated relative to thearm 806 to fold and/or retract the landing stand 820 to a lower profileconfiguration, thereby maintaining the same position both during flightand during landing. In some embodiments, the landing stand 820 and thecorresponding arm 806 are integrally formed. In some embodiments, thelanding stand 820 is coupled to the corresponding arm 806. For example,a process for assembling the UAV 800 may comprise mechanically couplingthe landing stand 820 to its corresponding arm 806. In some embodiments,the UAV 800 may comprise a mechanical and/or electrical connector at theconnection portion between the arm 806 and the landing stand 820. Forexample, the UAV 800 may comprise a connector 840 comprising matingconnection portions for providing mechanical and/or electricalconnection between the landing stand 820 and the corresponding arm 806.In some embodiments, the connector 840 can comprise correspondingmechanical and/or electrical mating portions, such as female and maleconnectors for physical and/or electrical connection between mechanicalcomponents and/or electrical components (e.g., electrical wiring) of thelanding stand 820 and the arm 806.

Referring to FIG. 8, in some embodiments, at least a portion of each ofthe arms 806 and at least a portion of each of the landing stands 820may be outside of a keep-out zone 810. In some embodiments, each of thelanding stands 820 may be perpendicular or substantially perpendicularto its corresponding arm 806. For example, the angle denoted as “Θ” inFIG. 8 may be 90°. As shown in FIG. 8, each of the landing stands 820may extend perpendicularly or substantially perpendicularly from aportion of the arm 806 outside of the keep-out zone 810 such that thelanding stands 820 are entirely or substantially entirely outside of thekeep-out zone 810. For example, the landing stand 820 may extend fromthe corresponding arm 806 from a position laterally further away fromthe central body 802 than the rotor disk of the rotor blades 808 coupledto the arm 806. In some embodiments, a landing stand 820 may extenddownward from a distal end of the arm 806. The UAV 800 may comprise asensor 822 on a portion of each of the landing stands 820 that isoutside of the keep-out zone 810. In some embodiments, the UAV 800 maycomprise both a sensor 818 on a portion of each of the arms 806 outsideof the keep-out zone 810 and a sensor 822 on a portion of each of thelanding stands 822 outside of the keep-out zone 810.

In some embodiments, a landing stand may extend perpendicularly orsubstantially perpendicularly from a corresponding arm such that only aportion of the landing stand is outside of a keep-out zone. In someembodiments, a landing stand may be fixedly coupled to, or integrallyformed with and extend rigidly from, a distal end of an arm such thatonly a portion of the landing stand is outside of a keep-out zone of theUAV. For example, the UAV may comprise a sensor on a portion of thelanding stand outside of the keep-out zone, such as on a surface of thelanding stand facing away from the central body and outside of thekeep-out zone. In some embodiments, a landing stand may extendperpendicularly or substantially perpendicularly from a distal end ofeach of the arms of a UAV, and a sensor may be positioned on a portionof each of the landing stands outside of the keep-out zone of the UAV.

In some embodiments, a landing stand may extend from a corresponding armat an angle other than 90°. For example, a landing stand may be fixedlycoupled to, or integrally formed with and extend rigidly from, acorresponding arm at an angle greater than 90°. In some embodiments, alanding stand may extend from a portion of the UAV other than an arm.The landing stand may extend from a portion of a central body of theUAV, for example being integrally formed with the central body orfixedly coupled to the central body. In some embodiments, the landingstand may extend from the central body at an angle greater than 90° suchthat a portion of the landing stand proximal to the central body isinside the keep-out zone and a distal portion of the landing stand awayfrom the central body is outside of the keep-out zone.

FIG. 9 Part A is a schematic side view of an arm 806 and a correspondinglanding stand 820 fixedly extending from the arm 806. As describedherein, the UAV 800 may comprise both a sensor 818 on a portion of thearm 806 outside of the keep-out zone 810 and a sensor 822 on a portionof the landing stand 822 outside of the keep-out zone 810. The arm 806may comprise a proximal portion 806A proximate to the central body 802and a distal portion 806B away from the central body 802, where thedistal portion 806B comprises a portion 806C outside of the keep-outzone 810. The sensor 818 may be positioned on the portion 806C of thearm 806 outside of the keep-out zone 810, such as at a distal end 806Dof the arm 806. The landing stand 820 is shown in FIG. 9 Part A as beingentirely outside of the keep-out zone 810. The landing stand 820 mayextend perpendicularly or substantially perpendicularly from the portion806C of the arm 806 such that the landing stand 820 is entirely outsideof the keep-out zone 810. In some embodiments, the sensor 822 may bepositioned on various portions of the landing stand 820. In someembodiments, the sensor 822 can be on a proximal portion 820A of thelanding stand 820 proximate to the arm 806, rather than on a distalportion 820B away from the arm 806, such that the sensor 822 is furtheraway from a landing surface. Positioning a sensor 822 on a proximalportion 820A of the landing stand 820 may eliminate or reduce damage tothe sensor 822 when the UAV 800 is landing. In some embodiments, thesensor 822 may be on a portion of the landing stand 820 facing away fromthe central body 802 to reduce or eliminate interference. In someembodiments, the sensor 822 may be on a surface of the landing stand 820opposite that facing the central body 802.

FIG. 9 Part B is a schematic side cross-sectional view of an arm 806 anda corresponding landing stand 820 fixedly extending from the arm 806. Insome embodiments, the arm 806 comprises at least a portion that ishollow such that at least a portion of the wiring 830 to providecommunication between one or more controllers of the UAV 800 and/or tosupply electrical power to a sensor may be housed within the arm 806. Insome embodiments, the landing stand 820 comprises at least a portion ofwhich that is hollow such that at least a portion of the wiring 830 toprovide communication between one or more controllers of the UAV 800 anda sensor may be housed within the landing stand 820. In someembodiments, both the arm 806 and the landing stand 820 can comprise atleast a portion of which that is hollow such that the wiring 830 mayextend from the central body to the sensor 818 and the sensor 822. Forexample, the sensor 818 may be at a distal end 806D of the arm 806 andan entire length of the arm 806 may be hollow such that wiring 830 forcommunication between the sensor 818 and one or more controllers housedwithin the central body 802 may extend from the central body 802 to thesensor 818 through the hollow shaft within the arm 806. At least aportion of the landing stand 802 may be hollow such that wiring 830 mayextend through at least a portion of the landing stand 820 for providingcommunication between the sensor 822 and one or more controllers withinthe central body 802. For example, the wiring 830 may extend from thecentral body 802 through at least a portion of the arm 806 and at leasta portion of the landing stand 820 to connect the sensor 822 with one ormore controllers. In some embodiments, wiring for providingcommunication between controllers within the central body 802 and thesensors may not be routed through the arm 806 or the landing stand 820.In some embodiments, the arm 806 and the landing stand 820 are nothollow and the wiring 830 is routed along an outer surface of the arm806 and the landing stand 820, such as being wrapped around the outersurface and the landing stand 820. In some embodiments, the wiring 830may comprise a first portion which extends from the central body to aconnection portion between the arm 806 and the landing stand 820, and asecond portion which extends from the connection portion to the sensor822. In some embodiments, the first and second portions of the wiring830 may be mechanically and electrically coupled together such that anelectrical signal can travel between the central body to the sensor 822on the landing stand 820. For example, the mechanical coupling maycomprise mechanical mating between respective ends of the first andsecond portions of the wiring 830. In some embodiments, the electricalcoupling may be via an electrical and/or electronic interface. Forexample, an electrical and/or electronic interface may comprise aUniversal Serial Bus (USB) interface, an auxiliary interface,combinations thereof and/or the like. In some embodiments, theelectrical and/or electronic interface can provide one way or two waycommunication.

FIG. 10 is a schematic side cross-sectional view of an example of a UAV1000 comprising a landing stand 1020 which is rotatably coupled to acentral body 1002 of the UAV 1000. The UAV 1000 may comprise an arm 1006extending outwardly from the central body 1002. As shown in FIG. 10, anarm 1006 may extend outwardly from each of opposing lateral surfaces ofthe central body 1002. Each of the arms 1006 may be coupled to acorresponding set of rotor blades 1008. In some embodiments, apropulsion unit of the UAV 1000 is at or substantially at a distal endof the arm 1006. For example, each of the set of rotor blades 1008 maybe coupled to a distal end portion of the arms 1006. The central body1002 may be coupled to a pair of landing stands 1020, and a sensor 1022may be positioned on a portion of each of the landing stands 1020. Eachof the landing stands 1020 may be rotatably coupled to the central body1002 at a pivot portion 1026. The landing stand 1020 may be rotatedaround the pivot portion 1026 such that the landing stand 1020 can berotated relative to the central body 1002. For example, a landing stand1020 may be rotated closer to an arm 1006 or rotated away from the arm1006. FIG. 10 shows each of the landing stands 1020 rotated away fromthe arms 1006, for example in an extended state. The landing stand 1020may be in an extended state when the landing stand 1020 is in use, suchas when the UAV 1000 is preparing for landing or when the UAV 1000 is ona landing surface. As shown in FIG. 10, each of the landing stands 1020in the extended state may be entirely within or substantially entirelywithin the keep-out zone 1010.

FIG. 11 Part A shows the UAV 1000 having the landing stand 1020 rotatedtoward the central body 1002, for example in a retracted state. Thelanding stand 1020 may be in the retracted state when the landing stand1020 is not in use, such as during flight. In the retracted state, thelanding stand 1020 may comprise a proximal portion 1020A proximate tothe central body 1002 which is within the keep-out zone 1010, and adistal portion 1020B away from central body 1002 which is outside of thekeep-out zone 1010. A sensor 1022 may be positioned on a portion of eachof the landing stands 1020 that can be outside of the keep-out zone 1010when the landing stand 1020 is in the retracted state. In someembodiments, the sensor 1022 can be positioned on a portion of thelanding stand 1020 facing away from the central body 1002. For example,a protrusion 1024 on the distal portion 1020B of the landing stand 1020may be outside of the keep-out zone 1010 when the landing stand 1020 isin the retracted state. The sensor 1022 may be on the protrusion 1024such that the sensor 1022 can be outside of the keep-out zone 1010 whenthe landing stand 1020 is in the retracted state. In some embodiments,the sensor 1022 can be positioned on a portion of the protrusion 1024facing away from the central body 1002, including on a surface of theprotrusion 1024 opposite that facing the central body 1002.

FIG. 11 Part B is a schematic side cross-sectional view of the UAV 1000in a retracted state, where the landing stands 1020 may comprise atleast a portion of which that is hollow such that the wiring 1030 toprovide communication between one or more controllers of the UAV 1000and the sensors 1022 and/or supply electrical power to the sensors 1022may be housed at least partially within the landing stands 1020. Forexample, at least a portion of the landing stands 1020, including atleast a portion of the protrusions 1024 on which the sensors 1022 arepositioned, may be hollow such that wiring 1030 from one or morecomponents within the central body 1002 may be entirely or substantiallyentirely enclosed within one or more portions of the UAV 100. Forexample, the portion of the wiring 1030 extending through the landingstands 1020 may be entirely housed within the landing stands 1020. Insome embodiments, each of the landing stands 1020 comprises at least aportion which is not hollow such that at least a portion of the wiring1030 is routed along an outer surface of the landing stand 1020, such asbeing wrapped around the outer surface. In some embodiments, each of thelanding stands 1020 is not hollow. In some embodiments, the wiring 1030is route entirely or substantially entirely along an outer surface ofeach of the landing stands 1020.

FIG. 12 is a top down schematic diagram of another example of a UAV1200. The UAV 1200 may have one or more properties as described herein.For example, the UAV 1200 may include a central body 1202, an arm 1206extending from each of four lateral surfaces of the central body 1202and a corresponding set of rotor blades 1208 coupled to each of the arms1206. The UAV 1200 may also comprise a plurality of protective covers1220. The protective covers 1220 may be configured to provide physicalprotection for each of the rotor blades 1208 and/or other portions ofthe UAV 1200 from impact by another object. For example, the UAV 1200may comprise a protective cover 1220 for each of the sets of rotorblades 1208 from collision with another object or surface during flightor landing, thereby reducing or preventing damage to the rotor blades1208. In some embodiments, the protective covers 1220 can provideprotection from external impact for both the sets of rotor blades 1208and the central body 1202 of the UAV. In some embodiments, each of theprotective covers 1220 may be coupled to a corresponding arm 1206. Forexample, a protective cover 1220 may be coupled to a corresponding arm1206 such that the protective cover 1220 can provide protection for theset of rotor blades 1208 coupled to the arm 1206. A protective cover1220 may be positioned relative to a corresponding rotor disk so as toprovide desired protection for the corresponding set of rotor blades1208 without impeding spinning of the rotor blades 1208. In someembodiments, each of the protective covers 1220 may partially surroundthe rotor disk of the corresponding set of rotor blades 1208. Forexample, the protective covers 1220 may comprise a partial ring shape,and may be positioned proximate and/or adjacent to the rotor disk of thecorresponding set of rotor blades 1208 such that protective cover 1220partially surrounds the rotor disk of the rotor blades 1208. In someembodiments, the protective cover 1220 may have a thickness and/orheight configured to provide desired protection for the correspondingset of rotor blades 1208. In some embodiments, a height of at least aportion of a protective cover 1220 may be the same or greater than aheight of a corresponding portion of the rotor disk of the correspondingrotor blades 1208. The protective covers 1220 may be oriented relativeto the corresponding set of rotor blades 1208 to provide desiredphysical protection for the rotor blades 1208 when the UAV 1200 comesinto contact with another object. In some embodiments, each of theprotective covers 1220 may be positioned proximate to or adjacent to therotor disk of the corresponding set of rotor blades and oriented suchthat at least a portion of each of the protective covers 1220 is furtheraway from the central body 1202 than any edge of the rotor disk. Forexample, each of the protective covers 1220 may be oriented such thatthe openings of the protective covers 1220 are positioned closest to thecentral body 1202 and the partial ring portions of the protective covers1220 are positioned away from the central body 1202. As shown in FIG.12, in some embodiments, the protective covers 1220 may comprise a halfring shape and the openings of the protective covers 1220 are positionedproximate to the central body 1202.

In some embodiments, the UAV 1200 may comprise a sensor 1218 on aportion of a protective cover 1220. A sensor 1218 may be positioned oneach of the protective covers 1220. In some embodiments, the sensors1218 may be positioned on a portion of a protective cover 1220 outsideof the keep-out zone 1210. The keep-out zone 1210 may have one or morefeatures as described herein. As described herein, the keep-out zone1210 may comprise a rotor blades spin space 1412 for each set of rotorblades 1208, and an interference space 1214. A rotor blades spin space1412 may comprise the rotor disk of the corresponding set of rotorblades 1208. In some embodiments, a rotor blades spin space 1412 can bethe rotor disk of the corresponding set of rotor blades 1208. Theinterference space 1214 may comprise a lateral boundary comprising sides1216 extending between adjacent sets of rotor blades 1208 of the UAV1200. The connection portions 1204 of adjacent lateral surfaces of thecentral body 1202 may be on corresponding sides 1216 of the lateralboundary of the interference space 1214. In some embodiments, theconnection portions 1204 of adjacent lateral surfaces of the centralbody 1202 are completely within the interference space 1214 such thatthe central body 1202 is completely within the interference space 1214.In some embodiments, the sensors 1218 may be positioned on a portion ofthe protective covers 1220 outside of both the rotor blades spin spaces1212 and the interference space 1214. In some embodiments, one or moreof the sensors 1218 may be positioned on a portion of the protectivecover 1220 facing away from the rotor blades 1208 and/or the centralbody 1202. In some embodiments, one or more of the sensors 1218 may bepositioned on a portion of the protective cover 1220 opposite a portionfacing the rotor blades 1208 and/or the central body 1202. In someembodiments, each of the protective covers 1220 of the UAV 1200comprises a sensor 1218 on a portion of the protective covers 1220furthest away from the central body 1202, such as on a distal mostportion of the protective covers 1220 facing away from the central body1202.

Referring to FIG. 13, a top-down schematic diagram of one of theprotective covers 1220, and a set of corresponding rotor blades 1208coupled to an arm 1206, are shown. As shown in FIG. 13, in someembodiments, the UAV 1200 can comprise both the sensor 1218 on theprotective cover 1220 and a sensor 1222 on the arm 1206, the sensor 1218on the protective cover 1220 and the sensor 1222 on the arm 1206 bothbeing outside of the rotor blades spin space 1212 and the interferencespace 1214. The sensor 1218 may be positioned on a surface of theprotective cover facing away from the central body. For example, thesensor 1218 may be on a portion of the protective cover furthest awayfrom the central body and on a surface facing away from the centralbody. In some embodiments, the sensor 1222 may be positioned on a distalend of the arm 1206 furthest away from the central body. In someembodiments, the UAV 1200 may comprise a sensor 1222 on a portion ofeach of its arms 1206 outside of the keep-out zone 1210.

Referring to FIG. 14, a top-down schematic diagram of another example ofa protective cover 1230 is shown. The protective cover 1230 may becoupled to an arm 1206 and positioned proximate or adjacent to the rotordisk of the set of rotor blades 1208 coupled to the arm 1206. Theprotective cover 1230 may comprise a partial ring shape and may surroundmore than half of the perimeter of the rotor disk. The protective cover1230 may be positioned proximate or adjacent to the set of rotor blades1208 and oriented such that the opening in the partial ring of theprotective cover 1230 is closest to the central body. For example, theprotective cover 1230 may comprise a portion which extends around aportion of the rotor disk of the rotor blades 1208 opposite that closestto the central body. In some embodiments, the protective covers 1230 areconfigured to provide protection from external impact for both the rotorblades 1408 and the central body of the UAV. As shown in FIG. 14, insome embodiments, the UAV 1200 can comprise a sensor 1218 on theprotective cover 1230 and a sensor 1222 on the arm 1206. The sensor 1218may be positioned on a surface of the protective cover 1230 facing awayfrom the central body, including on a portion of the protective cover1230 furthest away from the central body. In some embodiments, the UAV1200 comprises both a sensor 1222 on a portion of the arm 1206 and asensor 1218 on protective cover 1230 outside of the keep-out zone 1210.For example, the UAV 1200 may comprise a sensor 1222 at a distal end ofthe arm 1206 furthest away from the central body 1202 and a sensor 1218on a portion of the protective cover 1230 facing away from the centralbody 1202, such that the sensors 1222 and 1218 are outside of both therotor blades spin space 1212 and the interference space 1214. In someembodiments, the UAV 1200 may comprise a sensor 1222 on a portion ofeach of its arms 1206 outside of the keep-out zone 1210.

FIG. 15 is schematic top-down view of another example of a UAV 1500comprising a plurality of protective covers 1520. The UAV 1500 maycomprise one or more properties as described herein. For example, theUAV 1500 may comprise a central body 1502. The lateral body 1502 maycomprise a quadrilateral shape such that an arm 1502 extends outwardlyfrom each of the four lateral surfaces of the central body 1502, and aset of rotor blades 1508 is coupled to each of the four arms 1502. TheUAV 1500 may also comprise a protective cover 1520 for each of the foursets of rotor blades 1508. The UAV 1500 may comprise a plurality ofsensors 1518 positioned on portions of the UAV 1500 outside of thekeep-out zone 1510. For example, a sensor 1518 may be positioned on eachof the protective covers 1520 outside of the rotor blades spin space1512 of the corresponding set of rotor blades 1508, and the interferencespace 1514. In some embodiments, a rotor blades spin space 1512 can bethe rotor disk of the corresponding set of rotor blades 1508. Theinterference space 1514 may comprise a lateral boundary comprising sides1516 extending between adjacent sets of rotor blades 1508 of the UAV1500. One or more of the sensors 1518 may be positioned on a portion ofa protective cover 1520 facing away from the central body 1502, forexample on a portion of a protective cover 1520 furthest and facing awayfrom the central body. In some embodiments, one or more of theprotective covers 1520 may be coupled to a corresponding arm 1506. Insome embodiments, one or more of the protective covers 1520 may becoupled to the central body 1502. As shown in FIG. 15, a protectivecover 1520 may completely surround a rotor disk of a corresponding setof rotor blades 1508. For example, each of the protective covers 1520may be placed adjacent to or proximate to each of the rotor disks suchthat each of the protective covers 1520 completely surrounds theperimeter of each corresponding rotor disk. For example, the protectivecover 1520 may have a ring shape. In some embodiments, the protectivecovers 1520 may be configured to provide protection for the UAV 1500. Insome embodiments, the protective covers 1520 can be configured toprovide protection from external impact for both the sets of rotorblades 1508 and the central body 1502.

In some embodiments, a protective cover 1520 may have a thickness and/orheight configured to provide desired protection for the correspondingset of rotor blades 1508. In some embodiments, a protective cover 1520may have a thickness and/or height configured to provide desiredprotection for the central body 1502. In some embodiments, as describedherein, a height of at least a portion of a protective cover 1520 may bethe same or greater than a height of a corresponding portion of acorresponding rotor disk.

In some embodiments, each of the protective covers 1520 may comprise aportion which extends over at least a portion of the central body 1502.In some embodiments, each of the protective covers 1520 of the UAV 1500may comprise a portion which extends laterally beyond and away from thelateral periphery of the central body 1502. For example, each of theprotective covers 1520 may comprise a portion which extends beyond thelateral periphery away from the central body 1502 along all four sidesof the central body 1502, such that the protective covers 1520 areconfigured to provide protection for both the rotor blades 1508 and thecentral body 1502 from external impact. In some embodiments, portions ofthe protective covers 1520 may be positioned laterally beyond and awayfrom the central body 1502 around or substantially around a lateralperiphery of the central body. In some embodiments, a portion of each ofthe protective covers 1520 are positioned laterally further away fromthe central body 1502 than any portion of propulsion units, includingthe rotor blades 1508 and/or rotors of the propulsion units, and of theplurality of arms 1506.

In some embodiments, one or more protective covers may have variousconfigurations for providing desired protection to one or more of apropulsion unit, including the rotors and/or rotor blades of thepropulsion unit, a central body and an arm of the UAV. In someembodiments, a protective cover may partially surround a rotor disk of acorresponding set of rotor blades. In some embodiments, a protectivecover may partially surround a rotor disk of a corresponding set ofrotor blades. In some embodiments, one or more protective covers areconfigured to surround or substantially surround the central body, theplurality of arms, and the plurality of rotors of the UAV. In someembodiments, one or more protective covers of a UAV may be coupled toone or more of an arm and a central body of the UAV. In someembodiments, a protective cover may be coupled only to one or more armsof the UAV or only to the central body of the UAV. In some embodiments,a protective cover may be coupled to a distal end of an arm. In someembodiments, a protective cover may comprise at least a portion of whichthat is hollow such that wiring for communication between controllers ofthe UAV and one or more sensors positioned on the protective cover, suchas electrical wiring, may be routed through at least a portion of theprotective cover. For example, at least a portion of the wiring may behoused within the protective cover. In some embodiments, wiring forcommunication between one or more sensors on a protective cover may becompletely or substantially completely housed within the protectivecover and/or one or more other components of the UAV. In someembodiments, a protective cover may not be hollow. In some embodiments,wiring for communication between one or more sensors on the protectivecover and one or more controllers in the central body of the UAV may berouted over, for example wrapped around, one or more external surfacesof the protective cover.

FIG. 16 shows schematic side cross-sectional views of an example of aprotective cover 1620. One or more protective covers may comprise atleast a portion having the schematic side cross-sectional view describedwith reference to FIG. 16, including for example, the protective coversdescribed with reference to one or more of FIGS. 12-15. The protectivecover 1620 may have a first surface 1622 facing a corresponding set ofrotor blades and a second opposing surface 1624 facing away from thecorresponding set of rotor blades. In some embodiments, the protectivecover 1620 may comprise one or more features configured to providephysical protection for one or more sensors positioned on the protectivecover 1620. Referring to Part A of FIG. 16, a sensor 1626 may extendfrom the second opposing surface 1624 of the protective cover 1620. Insome embodiments, the second opposing surface 1624 may comprise aconcave curvature to provide protection for the sensor 1626. Forexample, at least a portion of the sensor 1626 may be within the recessformed by the concavity. In some embodiments, the sensor 1626 may bepositioned completely or substantially completely within the concavityon the second opposing surface 1624 of the protective cover 1620.Positioning a sensor within the concavity on the second opposing surface1624 may provide structural support and/or protection for the sensor,for example reducing exposure of the sensor 1626 to external elements.Referring to Part B of FIG. 16, in some embodiments, the protectivecover 1620 may comprise a protective shield 1628 over at least a portionof the second opposing surface 1624. For example, the protective shield1628 may extend over at least a portion of the second opposing surface1624 such that the protective shield 1628 extends over and encloses thesensor 1626. The protective shield 1628 may provide added physicalprotection for the sensor 1626 to further reduce or eliminate exposureof the external elements, such as impact with another object and/orenvironmental elements.

In some embodiments, one or more portions of the protective cover 1620can be shaped to improve the ability of the sensor 1626 to measure oneor more environmental parameters. In some embodiments, one or moreportions of the protective cover 1620 can have a curvature to providedesired reflection of light, sound and/or radio waves transmitted byand/or received by the sensor 1626. In some embodiments, the protectivecover 1620 can comprise a parabolic reflector to facilitate measurementof environmental parameters by the sensor 1626. At least a portion ofthe protective cover 1620 may be a parabolic reflector such that theability of the sensor 1626 positioned on, adjacent to and/or extendingfrom, the second opposing surface 1624 of the protective cover 1620 tomeasure one or more environmental parameters may be enhanced. In someembodiments, the second opposing surface 1624 can be shaped such that atleast a portion of the second opposing surface 1624 forms a parabolicreflector. For example, the second surface 1624 may comprise a parabolicreflector to enhance the quality of measurements made by image,ultrasonic and/or GPS sensors.

FIG. 17 is an example flow diagram of a process 1700 of assembling a UAVhaving one or more features described herein. In block 1702 at least onesensor is provided. As described herein, in some embodiments, the atleast one sensor may comprise an image sensor, ultrasonic sensor and/ora GPS sensor. In block 1704, the at least one sensor may be attached toa portion of a UAV to collect information regarding the environmentsurrounding the UAV, where the portion of the UAV is outside of akeep-out zone. In some embodiments, the at least one sensor comprisesone or more of an ultrasonic sensor, an image sensor and a GPS sensor.As described herein, a UAV comprising one or more sensors positionedoutside of the keep-out zone can demonstrate improved obstacle avoidancecapabilities, for example due to reduction or elimination ofinterference to the measurements made by the sensor from the UAV,thereby improving the quality of information collected by the sensors.Such a UAV may demonstrate improved ability to collect informationregarding its surrounding environment.

FIG. 18 is another example flow diagram of a process 1800 of assemblinga UAV having one or more features described herein. In block 1802, aplurality of sensors can be provided. In block 1804, each of theplurality of sensors can be attached to a respective portion of an arm,a landing stand, or a protective cover of a UAV to collect informationregarding the environment surrounding the UAV, where the respectiveportion of the arm, landing stand, and protective UAV is outside of akeep-out zone.

FIG. 19 illustrates a movable object 1900 including a carrier 1902 and apayload 1904, in accordance with embodiments. Although the movableobject 1900 is depicted as an aircraft, this depiction is not intendedto be limiting, and any suitable type of movable object can be used, aspreviously described herein. One of skill in the art would appreciatethat any of the embodiments described herein in the context of aircraftsystems can be applied to any suitable movable object (e.g., a UAV),including a UAV as described herein. In some instances, the payload 1904may be provided on the movable object 1900 without requiring the carrier1902. The movable object 1900 may include propulsion mechanisms 1906, asensing system 1908, and a communication system 1910.

The propulsion mechanisms 1906 can include one or more of rotors,propellers, blades, engines, motors, wheels, axles, magnets, or nozzles,as previously described. For example, the propulsion mechanisms 1906 maybe self-tightening rotors, rotor assemblies, or other rotary propulsionunits, as disclosed elsewhere herein. The movable object may have one ormore, two or more, three or more, or four or more propulsion mechanisms.The propulsion mechanisms may all be of the same type. Alternatively,one or more propulsion mechanisms can be different types of propulsionmechanisms. The propulsion mechanisms 1906 can be mounted on the movableobject 1900 using any suitable means, such as a support element (e.g., adrive shaft) as described elsewhere herein. The propulsion mechanisms1906 can be mounted on any suitable portion of the movable object 1900,such on the top, bottom, front, back, sides, or suitable combinationsthereof.

In some embodiments, the propulsion mechanisms 1906 can enable themovable object 1900 to take off vertically from a surface or landvertically on a surface without requiring any horizontal movement of themovable object 1900 (e.g., without traveling down a runway). Optionally,the propulsion mechanisms 1906 can be operable to permit the movableobject 1900 to hover in the air at a specified position and/ororientation. One or more of the propulsion mechanism 1900 may becontrolled independently of the other propulsion mechanisms.Alternatively, the propulsion mechanisms 1900 can be configured to becontrolled simultaneously. For example, the movable object 1900 can havemultiple horizontally oriented rotors that can provide lift and/orthrust to the movable object. The multiple horizontally oriented rotorscan be actuated to provide vertical takeoff, vertical landing, andhovering capabilities to the movable object 1900. In some embodiments,one or more of the horizontally oriented rotors may spin in a clockwisedirection, while one or more of the horizontally rotors may spin in acounterclockwise direction. For example, the number of clockwise rotorsmay be equal to the number of counterclockwise rotors. The rotation rateof each of the horizontally oriented rotors can be varied independentlyin order to control the lift and/or thrust produced by each rotor, andthereby adjust the spatial disposition, velocity, and/or acceleration ofthe movable object 1900 (e.g., with respect to up to three degrees oftranslation and up to three degrees of rotation).

The sensing system 1908 can include one or more sensors that may sensethe spatial disposition, velocity, and/or acceleration of the movableobject 1900 (e.g., with respect to up to three degrees of translationand up to three degrees of rotation). The one or more sensors caninclude any of the sensors previously described herein, including GPSsensors, motion sensors, inertial sensors, proximity sensors, or imagesensors. The sensing data provided by the sensing system 1908 can beused to control the spatial disposition, velocity, and/or orientation ofthe movable object 1900 (e.g., using a suitable processing unit and/orcontrol module, as described below). Alternatively, the sensing system1908 can be used to provide data regarding the environment surroundingthe movable object, such as weather conditions, proximity to potentialobstacles, location of geographical features, location of manmadestructures, and the like.

The communication system 1910 enables communication with terminal 1912having a communication system 1914 via wireless signals 1916. Thecommunication systems 1910, 1914 may include any number of transmitters,receivers, and/or transceivers suitable for wireless communication. Thecommunication may be one-way communication, such that data can betransmitted in only one direction. For example, one-way communicationmay involve only the movable object 1900 transmitting data to theterminal 1912, or vice-versa. The data may be transmitted from one ormore transmitters of the communication system 1910 to one or morereceivers of the communication system 1912, or vice-versa.Alternatively, the communication may be two-way communication, such thatdata can be transmitted in both directions between the movable object1900 and the terminal 1912. The two-way communication can involvetransmitting data from one or more transmitters of the communicationsystem 1910 to one or more receivers of the communication system 1914,and vice-versa.

In some embodiments, the terminal 1912 can provide control data to oneor more of the movable object 1900, carrier 1902, and payload 1904 andreceive information from one or more of the movable object 1900, carrier1902, and payload 1904 (e.g., position and/or motion information of themovable object, carrier or payload; data sensed by the payload such asimage data captured by a payload camera). In some instances, controldata from the terminal may include instructions for relative positions,movements, actuations, or controls of the movable object, carrier and/orpayload. For example, the control data may result in a modification ofthe location and/or orientation of the movable object (e.g., via controlof the propulsion mechanisms 1906), or a movement of the payload withrespect to the movable object (e.g., via control of the carrier 1902).The control data from the terminal may result in control of the payload,such as control of the operation of a camera or other image capturingdevice (e.g., taking still or moving pictures, zooming in or out,turning on or off, switching imaging modes, change image resolution,changing focus, changing depth of field, changing exposure time,changing viewing angle or field of view). In some instances, thecommunications from the movable object, carrier and/or payload mayinclude information from one or more sensors (e.g., of the sensingsystem 1908 or of the payload 1904). The communications may includesensed information from one or more different types of sensors (e.g.,GPS sensors, motion sensors, inertial sensor, proximity sensors, orimage sensors). Such information may pertain to the position (e.g.,location, orientation), movement, or acceleration of the movable object,carrier and/or payload. Such information from a payload may include datacaptured by the payload or a sensed state of the payload. The controldata provided transmitted by the terminal 1912 can be configured tocontrol a state of one or more of the movable object 1900, carrier 1902,or payload 1904. Alternatively or in combination, the carrier 1902 andpayload 1904 can also each include a communication module configured tocommunicate with terminal 1912, such that the terminal can communicatewith and control each of the movable object 1900, carrier 1902, andpayload 1904 independently.

In some embodiments, the movable object 1900 can be configured tocommunicate with another remote device in addition to the terminal 1912,or instead of the terminal 1912. The terminal 1912 may also beconfigured to communicate with another remote device as well as themovable object 1900. For example, the movable object 1900 and/orterminal 1912 may communicate with another movable object, or a carrieror payload of another movable object. When desired, the remote devicemay be a second terminal or other computing device (e.g., computer,laptop, tablet, smartphone, or other mobile device). The remote devicecan be configured to transmit data to the movable object 1900, receivedata from the movable object 1900, transmit data to the terminal 1912,and/or receive data from the terminal 1912. Optionally, the remotedevice can be connected to the Internet or other telecommunicationsnetwork, such that data received from the movable object 1900 and/orterminal 1912 can be uploaded to a website or server.

FIG. 20 is a schematic illustration by way of block diagram of a system2000 for controlling a movable object, in accordance with embodiments. Amovable object may include a UAV as described herein. The system 2000can be used in combination with any suitable embodiment of the systems,devices, and methods disclosed herein. The system 2000 can include asensing module 2002, processing unit 2004, non-transitory computerreadable medium 2006, control module 2008, and communication module2010.

The sensing module 2002 can utilize different types of sensors thatcollect information relating to the movable objects in different ways.Different types of sensors may sense different types of signals orsignals from different sources. For example, the sensors can includeinertial sensors, GPS sensors, proximity sensors (e.g., lidar), orvision/image sensors (e.g., a camera). The sensing module 2002 can beoperatively coupled to a processing unit 2004 having a plurality ofprocessors. In some embodiments, the sensing module can be operativelycoupled to a transmission module 2012 (e.g., a Wi-Fi image transmissionmodule) configured to directly transmit sensing data to a suitableexternal device or system. For example, the transmission module 2012 canbe used to transmit images captured by a camera of the sensing module2002 to a remote terminal.

The processing unit 2004 can have one or more processors, such as aprogrammable processor (e.g., a central processing unit (CPU)). Theprocessing unit 2004 can be operatively coupled to a non-transitorycomputer readable medium 2006. The non-transitory computer readablemedium 2006 can store logic, code, and/or program instructionsexecutable by the processing unit 2004 for performing one or more steps.The non-transitory computer readable medium can include one or morememory units (e.g., removable media or external storage such as an SDcard or random access memory (RAM)). In some embodiments, data from thesensing module 2002 can be directly conveyed to and stored within thememory units of the non-transitory computer readable medium 2006. Thememory units of the non-transitory computer readable medium 2006 canstore logic, code and/or program instructions executable by theprocessing unit 2004 to perform any suitable embodiment of the methodsdescribed herein. For example, the processing unit 2004 can beconfigured to execute instructions causing one or more processors of theprocessing unit 2004 to analyze sensing data produced by the sensingmodule. The memory units can store sensing data from the sensing moduleto be processed by the processing unit 2004. In some embodiments, thememory units of the non-transitory computer readable medium 2006 can beused to store the processing results produced by the processing unit2004.

In some embodiments, the processing unit 2004 can be operatively coupledto a control module 2008 configured to control a state of the movableobject. For example, the control module 2008 can be configured tocontrol the propulsion mechanisms of the movable object to adjust thespatial disposition, velocity, and/or acceleration of the movable objectwith respect to six degrees of freedom. Alternatively or in combination,the control module 2008 can control one or more of a state of a carrier,payload, or sensing module.

The processing unit 2004 can be operatively coupled to a communicationmodule 2010 configured to transmit and/or receive data from one or moreexternal devices (e.g., a terminal, display device, or other remotecontroller). Any suitable means of communication can be used, such aswired communication or wireless communication. For example, thecommunication module 2010 can utilize one or more of local area networks(LAN), wide area networks (WAN), infrared, radio, WiFi, point-to-point(P2P) networks, telecommunication networks, cloud communication, and thelike. Optionally, relay stations, such as towers, satellites, or mobilestations, can be used. Wireless communications can be proximitydependent or proximity independent. In some embodiments, line-of-sightmay or may not be required for communications. The communication module2010 can transmit and/or receive one or more of sensing data from thesensing module 2002, processing results produced by the processing unit2004, predetermined control data, user commands from a terminal orremote controller, and the like.

The components of the system 2000 can be arranged in any suitableconfiguration. For example, one or more of the components of the system2000 can be located on the movable object, carrier, payload, terminal,sensing system, or an additional external device in communication withone or more of the above. Additionally, although FIG. 20 depicts asingle processing unit 2004 and a single non-transitory computerreadable medium 2006, one of skill in the art would appreciate that thisis not intended to be limiting, and that the system 2000 can include aplurality of processing units and/or non-transitory computer readablemedia. In some embodiments, one or more of the plurality of processingunits and/or non-transitory computer readable media can be situated atdifferent locations, such as on the movable object, carrier, payload,terminal, sensing module, additional external device in communicationwith one or more of the above, or suitable combinations thereof, suchthat any suitable aspect of the processing and/or memory functionsperformed by the system 2000 can occur at one or more of theaforementioned locations.

While preferred embodiments of the present invention have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. Numerousvariations, changes, and substitutions will now occur to those skilledin the art without departing from the invention. It should be understoodthat various alternatives to the embodiments of the invention describedherein may be employed in practicing the invention. It is intended thatthe following claims define the scope of the invention and that methodsand structures within the scope of these claims and their equivalents becovered thereby.

What is claimed is:
 1. An unmanned aerial vehicle (UAV), comprising: acentral body; a plurality of arms, each arm extending from the centralbody and comprising a top surface and a bottom surface, the plurality ofarms comprising a first arm and a second arm; a plurality of rotors,each rotor being controllable by one or more controllers, the pluralityof rotors comprising a first rotor and a second rotor, wherein the firstrotor is coupled to a top surface of the first arm and the second rotoris coupled to a bottom surface of the second arm; and a plurality ofsensors configured to detect one or more obstacles in an environment,the plurality of sensors comprising a first sensor and a second sensor,wherein the first sensor is disposed on a bottom surface of the firstarm and the second sensor is disposed on a top surface of the secondarm.
 2. The UAV of claim 1, wherein the plurality of sensors aredisposed outside of a keep-out zone defined by areas that are swept byrotor blades of the plurality of rotors.
 3. The UAV of claim 1, whereinat least one sensor of the plurality of sensors is located within arecess formed by a concavity on a top surface or a bottom surface of acorresponding arm, and the UAV further comprises: a shield configured tobe extended over the at least one sensor located within the recess toprovide protection to the at least one sensor.
 4. The UAV of claim 1,wherein the central body comprises a top central surface and a bottomcentral surface.
 5. The UAV of claim 4, wherein a third sensor of theplurality of sensors is disposed on the top central surface or thebottom central surface of the central body.
 6. The UAV of claim 5,wherein the third sensor is located within a recess formed by aconcavity on the top central surface or the bottom central surface, andthe UAV further comprises: a shield configured to be extended over thethird sensor located within the recess to provide protection to thethird sensor.
 7. The UAV of claim 1, further comprising: a plurality ofprotective covers, at least one of the plurality of protective coversconfigured to protect at least one of the plurality of rotors.
 8. TheUAV of claim 7, wherein the at least one of the plurality of protectivecovers is attached to the central body or the plurality of arms.
 9. TheUAV of claim 1, wherein at least one sensor of the plurality of sensorsis located within a hollow portion of at least one arm of the pluralityof arms.
 10. The UAV of claim 1, further comprising: one or more landingstands configured to be coupled to the central body or the plurality ofarms, the one or more landing stands being substantially perpendicularto a bottom central surface of the central body or bottom surfaces ofthe plurality of arms.
 11. The UAV of claim 10, wherein at least onesensor of the plurality of sensors is located within a hollow portion ofat least one landing stand of the one or more landing stands.
 12. TheUAV of claim 1, wherein the first sensor or the second sensor is animage sensor.
 13. An unmanned aerial vehicle (UAV), comprising: acentral body comprising a top central surface and a bottom centralsurface; a plurality of arms, each arm extending from the central bodyand comprising a top surface and a bottom surface, the plurality of armscomprising a first arm and a second arm; a plurality of rotors, eachrotor being controllable by one or more controllers, the plurality ofrotors comprising a first rotor and a second rotor, wherein the firstrotor is coupled to a top surface of the first arm and the second rotoris coupled to a bottom surface of the second arm; and a plurality ofsensors configured to detect one or more obstacles in an environment,wherein at least one sensor of the plurality of sensors is disposed onthe top central surface or the bottom central surface of the centralbody.
 14. The UAV of claim 13, wherein the at least one sensor of theplurality of sensors is located within a recess formed by a concavity onthe top central surface or the bottom central surface of the centralbody, and the UAV further comprises: a shield configured to be extendedover the at least one sensor located within the recess to provideprotection to the at least one sensor.
 15. The UAV of claim 13, whereinthe plurality of sensors further comprise a first sensor and a secondsensor, wherein the first sensor is disposed on a bottom surface of thefirst arm and the second sensor is disposed on a top surface of thesecond arm.
 16. The UAV of claim 15, wherein the first sensor or thesecond sensor is located within a recess formed by a concavity on thebottom surface of the first arm or the top surface of the second arm,and the UAV further comprises: a shield configured to be extended overthe first sensor or the second sensor located within the recess toprovide protection to the first sensor or the second sensor.
 17. The UAVof claim 13, further comprising: a plurality of protective covers, atleast one of the plurality of protective covers configured to protect atleast one of the plurality of rotors and being attached to the centralbody or the plurality of arms.
 18. The UAV of claim 13, wherein theplurality of sensors further comprise a third sensor and the UAV furthercomprises: one or more landing stands configured to be coupled to thecentral body or the plurality of arms, the one or more landing standsbeing substantially perpendicular to the bottom central surface orbottom surfaces of the plurality of arms, and wherein the third sensoris located within a hollow portion of at least one arm of the pluralityof arms or at least one landing stand of the one or more landing stands.19. The UAV of claim 13, wherein the at least one sensor of theplurality of sensors is an image sensor.
 20. An unmanned aerial vehicle(UAV), comprising: a central body; a plurality of arms, each armextending from the central body and comprising a first surface and asecond surface opposite to the first surface; a plurality of rotors,each rotor being controllable by one or more controllers, wherein arotor of the plurality of rotors is coupled to a first surface of an armof the plurality of arms; and a plurality of sensors configured todetect one or more obstacles in an environment, the plurality of sensorscomprising a first sensor and a second sensor, wherein the first sensoris disposed on a second surface of the arm and the second sensor isdisposed on a surface of the central body.